1. Field of the Invention
The invention relates to an improved mechanism for translational movement of the air slide of an oil or gas burner.
2. Description of Related Art
Fuel burners such as the gas and oil burners made by Peabody Engineering Corporation of Stamford, Conn. are used in electric power generating plants. These burners typically have an air register, which comprises the section of the burner which contains and controls air flow by means of a venturi to increase the rate of flow of air entering the burner. Air entering the air register is divided into two streams by a conical plate, an inner stream passing through a diffuser which imparts a swirling motion to the air to mix the air with fuel and controls flow direction. So-called secondary air is most of the combustion air which follows the venturi contour of the register.
Combustion air is admitted to or excluded from the register by a tubular air slide, which is wide open when the burner is in use. The tubular air slide is movable on guide bars between the fully open position and a closed position, either manually or automatically by means of pneumatic piston and cylinder assemblies.
In automatic arrangements which employ pneumatic piston and cylnder assemblies, combustion products from the burning fuel can be deposited on the pistons of the air slide, and a build-up of such combustion products, which are sticky and hard to remove, can cause the pistons to jam in a fixed position, preventing movement of the air slide. This condition can cause damage to the burner in various ways, as for example by causing overheating of burner components, blowing back, and burning out, as will be understood by those acquainted with fuel burner maintenance. The present invention relates to avoiding the problems caused by combustion product deposition on the moving parts of air slide actuating piston and cylinder assemblies.